Aluminum alloy surface microstructure etching solution and etching method
By using a specific aluminum alloy etching solution and a precise etching method, the problems of slow etching rate and poor precision of aluminum alloys have been solved, achieving efficient and high-precision aluminum alloy microstructure processing to meet micron-level precision requirements.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- XIAN UNIV OF TECH
- Filing Date
- 2024-06-24
- Publication Date
- 2026-05-29
Smart Images
Figure CN118653153B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of chemical product technology, specifically to an etching solution for microstructures on aluminum alloy surfaces, and also to an etching method for microstructures on aluminum alloy surfaces. Background Technology
[0002] Aluminum alloys are widely used due to their strong metallic texture, low density, and good corrosion resistance. Their main alloying elements are aluminum, magnesium, and silicon. However, their excellent corrosion resistance makes them ineffective for etching with conventional chemicals. Currently used aluminum alloy etching solutions are mainly composed of a mixture of phosphoric acid and nitric acid, which has a slow etching rate and poor precision. Therefore, there is a need for an aluminum alloy etching solution and method that offers both a faster etching rate and higher precision. Summary of the Invention
[0003] The first objective of this invention is to provide an etching solution for microstructures on aluminum alloy surfaces, which can etch aluminum alloys efficiently and with high precision.
[0004] The second objective of this invention is to provide a method for etching microstructures on the surface of aluminum alloys.
[0005] The first technical solution adopted in this invention is an etching solution for microstructures on aluminum alloy surfaces, comprising the following components: solvent and solute; the solvent is water, and the water contains the following components at concentrations: HCl 2.4mol / L-3.2mol / L, H2O2 2.4mol / L-4.8mol / L, HF 3.2mol / L-4.8mol / L, corrosion inhibitor 1g / L-10g / L, dispersant 20g / L-50g / L, and H2O2 stabilizer 5g / L-10g / L.
[0006] The invention is further characterized in that:
[0007] The corrosion inhibitor is chitosan or methylcellulose.
[0008] The dispersant is sodium octyl sulfate or sodium decaalkyl sulfate.
[0009] The H2O2 stabilizer is a mixture of magnesium sulfate and sodium silicate, wherein the mass ratio of magnesium sulfate to sodium silicate is 1:2.
[0010] The pH value of the etching solution is less than or equal to 2.
[0011] The second technical solution adopted in this invention is an etching method for the microstructure of aluminum alloy surfaces, comprising the following steps:
[0012] Step 1: Pre-treat the selected polished aluminum alloy substrate;
[0013] Step 2: Use an 18W-36W ultraviolet lamp in conjunction with a film mask for laser printing to expose the aluminum alloy substrate pretreated in Step 1 for 60-120 seconds, and develop it with a 1% sodium carbonate solution until the surface pattern is clear. Then rinse with water and blow dry.
[0014] Step 3: Use the aluminum alloy etching solution described above to etch the aluminum alloy substrate treated in Step 2 using a spray etching method. The spray pressure is 0.3MPa-0.6MPa; the etching time is 2-4 minutes, and the etching temperature is controlled at 20℃-25℃.
[0015] Step 4: After etching, rinse the aluminum alloy substrate with clean water and then soak it in a 5% NaOH solution at 20℃-30℃ to remove residual ink from the surface. After removing the surface ink, clean it with clean water and alcohol, and then dry it.
[0016] The invention is further characterized in that:
[0017] Step 1 is as follows:
[0018] Step 1.1: Soak the selected polished aluminum alloy substrate in anhydrous ethanol for 10-15 minutes to remove oil stains, and then dry it;
[0019] Step 1.2: Uniformly coat a layer of photosensitive ink onto the surface of the aluminum alloy substrate after the treatment in Step 1.1;
[0020] Step 1.3: Place the aluminum alloy substrate treated in Step 1.2 in a drying oven at 50℃-70℃ and dry for 60-90 minutes.
[0021] The beneficial effects of this invention are: the etching solution of this invention can etch aluminum alloys efficiently and with high precision, and the etching precision error can be less than 100μm, which can meet the requirements of micron-level precision machining. The etching rate can reach more than 40μm / mins, which is fast and low cost. Attached Figure Description
[0022] Figure 1 The image shows the macroscopic morphology of the etched sample surface in Example 6.
[0023] Figure 2 The laser confocal results are shown for the etched sample in Example 6.
[0024] Figure 3 The microstructure of the etched area in Example 6;
[0025] Figure 4 The Al element distribution in the etched region of Example 6;
[0026] Figure 5The distribution of O elements in the etched region in Example 6;
[0027] Figure 6 The distribution of Cl elements in the etched region in Example 6;
[0028] Figure 7 This shows the Mg element distribution in the etched region of Example 6. Detailed Implementation
[0029] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.
[0030] This invention provides an etching solution for microstructures on aluminum alloy surfaces, comprising the following components: the solvent is water, and the water contains the following components at the following concentrations: HCl 2.4mol / L-3.2mol / L, H2O2 2.4mol / L-4.8mol / L, HF 3.2mol / L-4.8mol / L, corrosion inhibitor 1g / L-10g / L, dispersant 20g / L-50g / L, and H2O2 stabilizer 5g / L-10g / L.
[0031] The corrosion inhibitor is chitosan or methylcellulose.
[0032] The dispersant is sodium octyl sulfate or sodium decaalkyl sulfate.
[0033] The H2O2 stabilizer is a mixture of magnesium sulfate and sodium silicate, wherein the mass ratio of magnesium sulfate to sodium silicate is 1:2.
[0034] The pH value of the etching solution is less than or equal to 2.
[0035] This invention also provides a method for etching microstructures on the surface of aluminum alloys, comprising the following steps:
[0036] Step 1: Pre-treat the selected polished aluminum alloy substrate;
[0037] Step 1 is as follows:
[0038] Step 1.1: Soak the selected polished aluminum alloy substrate in anhydrous ethanol for 10-15 minutes to remove oil stains, and then dry it;
[0039] Step 1.2: Uniformly coat a layer of photosensitive ink onto the surface of the aluminum alloy substrate after the treatment in Step 1.1;
[0040] Step 1.3: Place the aluminum alloy substrate treated in Step 1.2 in a drying oven at 50℃-70℃ and dry for 60-90 minutes.
[0041] Step 2: Use an 18W-36W ultraviolet lamp in conjunction with a film mask for laser printing to expose the aluminum alloy substrate pretreated in Step 1 for 60-120 seconds, and develop it with a 1% sodium carbonate solution until the surface pattern is clear. Then rinse with water and blow dry.
[0042] Step 3: Use the aluminum alloy etching solution described above to etch the aluminum alloy substrate treated in Step 2 using a spray etching method. The spray pressure is 0.3MPa-0.6MPa; the etching time is 2-4 minutes, and the etching temperature is controlled at 20℃-25℃.
[0043] Step 4: After etching, rinse the aluminum alloy substrate with clean water and then soak it in a 5% NaOH solution at 20℃-30℃ to remove residual ink from the surface. After removing the surface ink, clean it with clean water and alcohol, and then dry it.
[0044] The aluminum alloy etching solution described in this invention undergoes complex reactions during chemical etching, and the main chemical reaction equations are shown below:
[0045] 2Al + 6HCl = 2AlCl3 + 3H2
[0046] AlCl3 + H2O2 = Al(OH)3 + Cl2
[0047] 6HF + 2Al = 3H₂ + 2AlF₃
[0048] Si + 4HF = 2H₂ + SiF₄
[0049] The products after the reaction are precipitates and metal salts that can be removed by filtration or precipitation.
[0050] HCl provides chloride ions, which, through their strong coordination, promote the etching reaction of the metal by the etching solution. It also provides hydrogen ions, lowering the pH and accelerating the etching rate. H₂O₂ reduces the corrosion potential, making the reaction easier and thus accelerating the etching rate and improving the etching effect. The nitrogen atoms in chitosan molecules can chelate and adsorb with the metal, thus acting as a corrosion inhibitor. Furthermore, chitosan, as a degradation product of the natural product chitin, is abundant, inexpensive, and environmentally friendly, making its use as a corrosion inhibitor highly economical and consistent with the principles of "green chemistry." Sodium octyl sulfate forms hydrogen bonds or van der Waals forces with the surface of solid particles or droplets, dispersing them in water. In addition, sodium octyl sulfate can interact with surfactants to enhance the dispersion effect. Magnesium sulfate or sodium silicate can reduce the degradation rate of H₂O₂, making the reaction more stable and the etching solution more durable.
[0051] The present invention will be further described in detail below through embodiments:
[0052] Example 1
[0053] Under normal temperature conditions, each solute raw material was mixed evenly with water to prepare 1L of water-based aluminum alloy etching solution. The concentrations of each component were HCl 2.6 mol / L, H2O2 2.4 mol / L, HF 3.2 mol / L, chitosan 2g / L, sodium octyl sulfate 5g / L, magnesium sulfate 2g / L, and sodium silicate 2g / L.
[0054] Select one polished 6061 aluminum alloy substrate. Perform the following process:
[0055] (1) Use anhydrous ethanol to ultrasonically clean the 6061 aluminum alloy substrate for 10 minutes to remove oil stains, and then dry it.
[0056] (2) Apply a layer of photosensitive ink evenly.
[0057] (3) Place it in a drying oven at 70°C and dry for 90 minutes.
[0058] (4) Use a 36W ultraviolet lamp in conjunction with a film mask for laser printing to expose the pattern for 60 seconds, and develop it with a 1% sodium carbonate solution until the surface pattern is clear. Then rinse with water and blow dry.
[0059] (5) Use the above-mentioned aluminum alloy etching solution to etch the treated aluminum alloy substrate by spray etching for 2 minutes, control the etching temperature at 20 degrees and the spray pressure at 0.4 MPa.
[0060] (6) After etching, the aluminum alloy substrate is rinsed with clean water and then soaked in a 5% sodium hydroxide solution at 20°C to remove residual ink from the surface.
[0061] (7) After removing the surface ink, clean it with water and alcohol, and then dry it.
[0062] The mask pattern used has a linewidth of 0.6 mm, and the average linewidth after etching is 0.66 mm, with a depth of 0.08 mm and a precision error of 30 μm. This precision is better than the average level of general etching solutions. The etching rate is 40 μm / min, which is relatively fast. The etched area is flat and has uniform roughness, with an average roughness of Ra6.7, indicating good flatness.
[0063] Example 2
[0064] Under normal temperature conditions, mix all solute raw materials with water to prepare 1L of water-based aluminum alloy etching solution. The concentrations of each component are as follows: HCl 2.8 mol / L, H2O2 2.6 mol / L, HF 3.2 mol / L, methylcellulose 2g / L, sodium decaalkyl sulfate 5g / L, magnesium sulfate 2g / L, and sodium silicate 2g / L.
[0065] Select one polished 6061 aluminum alloy substrate. Perform the following process:
[0066] (1) Use anhydrous ethanol to ultrasonically clean the 6061 aluminum alloy substrate for 10 minutes to remove oil stains, and then dry it.
[0067] (2) Apply a layer of photosensitive ink evenly.
[0068] (3) Place it in a drying oven at 70°C and dry for 90 minutes.
[0069] (4) Use a 36W ultraviolet lamp in conjunction with a film mask for laser printing to expose the pattern for 60 seconds, and develop it with a 1% sodium carbonate solution until the surface pattern is clear. Then rinse with water and blow dry.
[0070] (5) Use the above-mentioned aluminum alloy etching solution to etch the treated aluminum alloy substrate by spray etching for 2 minutes, control the etching temperature at 25 degrees and the spray pressure at 0.5 MPa.
[0071] (6) After etching, the aluminum alloy substrate is rinsed with clean water and then soaked in a 5% sodium hydroxide solution at 30°C to remove residual ink from the surface.
[0072] (7) After removing the surface ink, clean it with water and alcohol, and then dry it.
[0073] The mask pattern used has a linewidth of 0.6 mm, and after etching, the average linewidth is 0.64 mm, the depth is 0.09 mm, and the accuracy error is 20 μm, which is better than the average level of general etching solutions. The etching rate is 45 μm / min, which is relatively fast. The etched area is flat and has uniform roughness, with an average roughness of Ra6.5, indicating good flatness.
[0074] Example 3
[0075] Under normal temperature conditions, mix all solute raw materials with water to prepare 1L of water-based aluminum alloy etching solution. The concentrations of each component are as follows: HCl 3.2 mol / L, H2O2 2.6 mol / L, HF 3.2 mol / L, chitosan 2g / L, sodium octyl sulfate 5g / L, magnesium sulfate 2g / L, and sodium silicate 2g / L.
[0076] Select one polished 6061 aluminum alloy substrate. Perform the following process:
[0077] (1) Use anhydrous ethanol to ultrasonically clean the 6061 aluminum alloy substrate for 10 minutes to remove oil stains, and then dry it.
[0078] (2) Apply a layer of photosensitive ink evenly.
[0079] (3) Place it in a drying oven at 70°C and dry for 90 minutes.
[0080] (4) Use a 36W ultraviolet lamp in conjunction with a film mask for laser printing to expose the pattern for 60 seconds, and develop it with a 1% sodium carbonate solution until the surface pattern is clear. Then rinse with water and blow dry.
[0081] (5) Use the above-mentioned aluminum alloy etching solution to etch the treated aluminum alloy substrate by spray etching for 2 minutes, control the etching temperature at 25 degrees and the spray pressure at 0.3 MPa.
[0082] (6) After etching, the aluminum alloy substrate is rinsed with clean water and then soaked in a 5% sodium hydroxide solution at 25°C to remove residual ink from the surface.
[0083] (7) After removing the surface ink, clean it with water and alcohol, and then dry it.
[0084] The mask pattern used has a linewidth of 0.6 mm, and after etching, the average linewidth is 0.71 mm, the depth is 0.11 mm, and the accuracy error is 55 μm, which is better than the average level of general etching solutions. The etching rate is 55 μm / min, which is relatively fast. The etched area is flat and has uniform roughness, with an average roughness of Ra6.2, indicating good flatness.
[0085] Example 4
[0086] Under normal temperature conditions, mix all solute raw materials with water to prepare 1L of water-based aluminum alloy etching solution. The concentrations of each component are: HCl 2.8 mol / L, H2O2 3.6 mol / L, HF 3.2 mol / L, chitosan 2g / L, sodium octyl sulfate 5g / L, magnesium sulfate 2g / L, and sodium silicate 2g / L.
[0087] Select one polished 6061 aluminum alloy substrate. Perform the following process:
[0088] (1) Use anhydrous ethanol to ultrasonically clean the 6061 aluminum alloy substrate for 10 minutes to remove oil stains, and then dry it.
[0089] (2) Apply a layer of photosensitive ink evenly.
[0090] (3) Place it in a drying oven at 70°C and dry for 90 minutes.
[0091] (4) Use a 36W ultraviolet lamp in conjunction with a film mask for laser printing to expose the pattern for 60 seconds, and develop it with a 1% sodium carbonate solution until the surface pattern is clear. Then rinse with water and blow dry.
[0092] (5) Use the above-mentioned aluminum alloy etching solution to etch the treated aluminum alloy substrate by spray etching for 2 minutes, control the etching temperature at 25 degrees and the spray pressure at 0.6 MPa.
[0093] (6) After etching, the aluminum alloy substrate is rinsed with clean water and then soaked in a 5% sodium hydroxide solution at 22°C to remove residual ink from the surface.
[0094] (7) After removing the surface ink, clean it with water and alcohol, and then dry it.
[0095] The mask pattern used has a linewidth of 0.6 mm, and after etching, the average linewidth is 0.67 mm, the depth is 0.09 mm, and the accuracy error is 35 μm, which is better than the average level of general etching solutions. The etching rate is 45 μm / min, which is relatively fast. The etched area is flat and has uniform roughness, with an average roughness of Ra6.2, indicating good flatness.
[0096] Example 5
[0097] Under normal temperature conditions, mix all solute raw materials with water to prepare 1L of water-based aluminum alloy etching solution. The concentrations of each component are as follows: HCl 2.8 mol / L, H2O 2 4.8 mol / L, HF 3.2 mol / L, chitosan 2g / L, sodium octyl sulfate 5g / L, magnesium sulfate 2g / L, and sodium silicate 2g / L.
[0098] Select one polished 6061 aluminum alloy substrate. Perform the following process:
[0099] (1) Use anhydrous ethanol to ultrasonically clean the 6061 aluminum alloy substrate for 10 minutes to remove oil stains, and then dry it.
[0100] (2) Apply a layer of photosensitive ink evenly.
[0101] (3) Place it in a drying oven at 70°C and dry for 90 minutes.
[0102] (4) Use a 36W ultraviolet lamp in conjunction with a film mask for laser printing to expose the pattern for 60 seconds, and develop it with a 1% sodium carbonate solution until the surface pattern is clear. Then rinse with water and blow dry.
[0103] (5) Use the above-mentioned aluminum alloy etching solution to etch the treated aluminum alloy substrate by spray etching for 2 minutes, control the etching temperature at 25 degrees and the spray pressure at 0.5 MPa.
[0104] (6) After etching, the aluminum alloy substrate is rinsed with clean water and then soaked in a 5% sodium hydroxide solution at 25°C to remove residual ink from the surface.
[0105] (7) After removing the surface ink, clean it with water and alcohol, and then dry it.
[0106] The mask pattern used has a linewidth of 0.6 mm, and after etching, the average linewidth is 0.67 mm, the depth is 0.09 mm, and the accuracy error is 35 μm, which is better than the average level of general etching solutions. The etching rate is 45 μm / min, which is relatively fast. The etched area is flat and has uniform roughness, with an average roughness of Ra6.3, indicating good flatness.
[0107] Example 6
[0108] Under normal temperature conditions, mix all solute raw materials with water to prepare 1L of water-based aluminum alloy etching solution. The concentrations of each component are: HCl 2.8 mol / L, H2O2 3.6 mol / L, HF 3.8 mol / L, chitosan 2g / L, sodium octyl sulfate 5g / L, magnesium sulfate 2g / L, and sodium silicate 2g / L.
[0109] Select one polished 6061 aluminum alloy substrate. Perform the following process:
[0110] (1) Use anhydrous ethanol to ultrasonically clean the 6061 aluminum alloy substrate for 10 minutes to remove oil stains, and then dry it.
[0111] (2) Apply a layer of photosensitive ink evenly.
[0112] (3) Place it in a drying oven at 70°C and dry for 90 minutes.
[0113] (4) Use a 36W ultraviolet lamp in conjunction with a film mask for laser printing to expose the pattern for 60 seconds, and develop it with a 1% sodium carbonate solution until the surface pattern is clear. Then rinse with water and blow dry.
[0114] (5) Use the above-mentioned aluminum alloy etching solution to etch the treated aluminum alloy substrate by spray etching for 2 minutes, control the etching temperature at 25 degrees and the spray pressure at 0.5 MPa.
[0115] (6) After etching, the aluminum alloy substrate is rinsed with clean water and then soaked in a 5% sodium hydroxide solution at 30°C to remove residual ink from the surface.
[0116] (7) After removing the surface ink, clean it with water and alcohol, and then dry it.
[0117] The mask pattern used has a line width of 0.6 mm, and the average line width after etching is 0.63 mm (e.g., Figure 1 As shown in the figure, the depth is 0.1 mm, the accuracy error is 15 μm, which is better than the average level of general etching solutions. The etching rate is 50 μm / min, which is relatively fast. The etched area is flat and has uniform roughness, with an average roughness of Ra5.3, indicating good flatness.
[0118] Figure 1 and Figure 2 The images show optical microscopy and laser confocal microscopy images of the sample after etching in Example 6. It can be seen that the etched flow channels are straight and have relatively uniform depth, indicating a good etching effect. Figure 3 The image shows a SEM image of the etched area of the sample in Example 6. It can be seen that the main corrosion mode is uniform corrosion. Figure 4 , Figure 5 , Figure 6 and Figure 7 The figure shows the distribution of Al, O, Cl, and Mg elements in the etched area of the sample in Example 6. It can be seen that the distribution of different elements is relatively uniform after etching, indicating that no selective etching occurs during the etching process using this etching solution, which can ensure the smoothness of the etched area surface as much as possible.
[0119] Example 7
[0120] Under normal temperature conditions, mix all solute raw materials with water to prepare 1L of water-based aluminum alloy etching solution. The concentrations of each component are as follows: HCl 2.8 mol / L, H2O 2 3.6 mol / L, HF 4.8 mol / L, chitosan 2g / L, sodium octyl sulfate 5g / L, magnesium sulfate 2g / L, and sodium silicate 2g / L.
[0121] Select one polished 6061 aluminum alloy substrate. Perform the following process:
[0122] (1) Use anhydrous ethanol to ultrasonically clean the 6061 aluminum alloy substrate for 10 minutes to remove oil stains, and then dry it.
[0123] (2) Apply a layer of photosensitive ink evenly.
[0124] (3) Place it in a drying oven at 70℃ and dry for 90 minutes.
[0125] (4) Use a 36W ultraviolet lamp in conjunction with a film mask for laser printing to expose the pattern for 60 seconds, and develop it with a 1% sodium carbonate solution until the surface pattern is clear. Then rinse with water and blow dry.
[0126] (5) The treated aluminum alloy substrate was etched for 2 minutes using the above aluminum alloy etching solution by spray etching, with the etching temperature controlled at 22 degrees and the spray pressure at 0.5 MPa.
[0127] (6) After etching, the aluminum alloy substrate is rinsed with clean water and then soaked in a 5% sodium hydroxide solution at 20°C to remove residual ink from the surface.
[0128] (7) After removing the surface ink, clean it with water and alcohol, and then dry it.
[0129] The mask pattern used has a linewidth of 0.6 mm, and the average linewidth after etching is 0.65 mm, with a depth of 0.11 mm and a precision error of 25 μm. This precision is better than the average level of general etching solutions. The etching rate is 55 μm / min, which is relatively fast. The etched area is flat and has uniform roughness, with an average roughness of Ra5.4, indicating good flatness.
[0130] Example 8
[0131] Under normal temperature conditions, mix all solute raw materials with water to prepare 1L of water-based aluminum alloy etching solution. The concentrations of each component are: HCl 2.8 mol / L, H2O2 3.6 mol / L, HF 3.8 mol / L, chitosan 2g / L, sodium octyl sulfate 5g / L, magnesium sulfate 2g / L, and sodium silicate 2g / L.
[0132] Select one polished 6061 aluminum alloy substrate. Perform the following process:
[0133] (1) Use anhydrous ethanol to ultrasonically clean the 6061 aluminum alloy substrate for 10 minutes to remove oil stains, and then dry it.
[0134] (2) Apply a layer of photosensitive ink evenly.
[0135] (3) Place it in a drying oven at 70°C and dry for 90 minutes.
[0136] (4) Use a 36W ultraviolet lamp in conjunction with a film mask for laser printing to expose the pattern for 60 seconds, and develop it with a 1% sodium carbonate solution until the surface pattern is clear. Then rinse with water and blow dry.
[0137] (5) Use the above-mentioned aluminum alloy etching solution to etch the treated aluminum alloy substrate by spray etching for 2 minutes, control the etching temperature at 25 degrees and the spray pressure at 0.5 MPa.
[0138] (6) After etching, the aluminum alloy substrate is rinsed with clean water and then soaked in a 5% sodium hydroxide solution at 20°C to remove residual ink from the surface.
[0139] (7) After removing the surface ink, clean it with water and alcohol, and then dry it.
[0140] The mask pattern used has a linewidth of 0.6 mm, and after etching, the average linewidth is 0.72 mm, the depth is 0.13 mm, and the accuracy error is 51 μm, which is better than the average level of general etching solutions. The etching rate is 65 μm / min, which is relatively fast. The etched area is flat and has uniform roughness, with an average roughness of Ra6.5, indicating good flatness.
Claims
1. An etching solution for microstructures on aluminum alloy surfaces, characterized in that, The following components are included, including solvent and solute: The solvent is water, which contains the following components at the following concentrations: HCl 2.4mol / L-3.2mol / L, H2O2 2.4mol / L-4.8mol / L, HF 3.2mol / L-4.8mol / L, corrosion inhibitor 1g / L-10g / L, dispersant 20g / L-50g / L, and H2O2 stabilizer 5g / L-10g / L. The corrosion inhibitor is chitosan or methylcellulose; The dispersant is sodium octyl sulfate or sodium decaalkyl sulfate; The H2O2 stabilizer is a mixture of magnesium sulfate and sodium silicate, wherein the mass ratio of magnesium sulfate to sodium silicate is 1:2; The pH value of the etching solution is less than or equal to 2.
2. A method for etching microstructures on the surface of aluminum alloys, characterized in that, Includes the following steps: Step 1: Pre-treat the selected polished aluminum alloy substrate; Step 2: Use an 18W-36W ultraviolet lamp in conjunction with a film mask for laser printing to expose the aluminum alloy substrate pretreated in Step 1 for 60-120 seconds, and develop it with a 1% sodium carbonate solution until the surface pattern is clear. Then rinse with water and blow dry. Step 1 is as follows: Step 1.1: Soak the selected polished aluminum alloy substrate in anhydrous ethanol for 10-15 minutes to remove oil stains, and then dry it; Step 1.2: Uniformly coat a layer of photosensitive ink onto the surface of the aluminum alloy substrate after the treatment in Step 1.1; Step 1.3: Place the aluminum alloy substrate treated in Step 1.2 in a drying oven at 50℃-70℃ and dry for 60-90 minutes; Step 3: Use the aluminum alloy etching solution described in claim 1 to etch the aluminum alloy substrate treated in step 2 using a spray etching method. The spray pressure is 0.3MPa-0.6MPa; the etching time is 2 minutes-4 minutes, and the etching temperature is controlled at 20℃-25℃. Step 4: After etching, rinse the aluminum alloy substrate with clean water and then soak it in a 5% NaOH solution at 20℃-30℃ to remove residual ink from the surface. After removing the surface ink, clean it with clean water and alcohol, and then dry it.